Summary The Progressive Aerodyne, Inc. SeaRey amphibious aircraft (serial number DK173, registration C-GCWR) was taking part in the Canadian Aviation Expo at the Oshawa Airport. The flight was planned as part of a two-plane demonstration with another SeaRey aircraft, registration C-GJIB. The plan was to take off in formation with C-GCWR leading, climb to 1000feet above ground level, turn left, and join a left downwind for Runway30. When south of the airport, the aircraft were to split and perform a coordinated series of non-aerobatic manoeuvres that had been briefed and practised. Before take-off, C-GCWR had radio problems, so C-GJIB led the take-off and C-GCWR was in a right-echelon wingman position. The aircraft were cleared to take off in formation on Runway30 from the intersection of Runway04/22. After take-off, the lead aircraft climbed out the extended centreline of the runway. C-GCWR made a left turn as if leaving the formation toward the southwest, then turned to the right to again follow the lead aircraft. C-GCWR then pitched nose up and appeared to stall and spin to the left. The propeller was turning as the aircraft descended. The aircraft continued in a descending turn to the left until it struck the ground in a residential construction area. The aircraft was destroyed, and the pilot was fatally injured. There was no post-impact fire. The accident took place at 1339 eastern daylight time at 4355'25"N, 7854'55"W. Ce rapport est galement disponible en franais. Other Factual Information The most recent weather report from the Oshawa Airport at 1300eastern daylight time1 was scattered cloud at 5000feet above ground level (agl), visibility 3statute miles in haze, wind 240True(T) at 10knots. Weather was not a factor in the accident. The pilot held a valid airline transport pilot licence, issued by Transport Canada, endorsed for single- and multi-engine land and sea aeroplanes, and a Group1 instrument rating. He had owned and operated C-GCWR since 2003and had accumulated about 280hours in it, with about 300landings on land and 400on water. The pilot was an experienced career airline pilot. He was known to be disciplined, and he had adeptly handled a previous critical emergency in this aircraft. Based on the autopsy and medical records, there was no indication that incapacitation or physiological factors affected his performance. Communications between the aircraft and air traffic control were reviewed. Transmissions from C-GCWR were garbled and unreadable when C-GCWR requested taxi clearance before the take-off. As a result, the lead changed to C-GJIB. C-GJIB obtained a take-off clearance for both aircraft and communicated with C-GCWR by hand signals, a normal practice in formation flying. Moments before impact, there was a three-second garbled transmission that was similar to earlier ones from C-GCWR. Nothing intelligible was discernable from the tape when it was analysed by the TSB Engineering Laboratory. The aircraft struck a mound of earth behind foundations of residential housing under construction. It was on an easterly heading with about 20degrees of left bank (all measurements are approximate). The left side of the fibreglass hull struck a concrete sewer casement that was protruding from the mound of earth. The aircraft stopped abruptly, nosing over into the depressed area between two mounds of earth. The cockpit came to rest nearly vertically and nose down. The aft fuselage buckled and continued beyond the vertical. Distance from the beginning of the ground scar to the nose was about 15feet. Beyond the second pile of earth was a 400-foot length of unobstructed roadway beyond which were 2000feet of driving range and a golf course. The cockpit area was essentially intact. The three-point harness tore out of the tubular aluminium frame at the common attachment point of the seat and shoulder belts. There was no indication of pre-impact structural damage. Flight controls were examined on site and found to be continuous and free. The elevator trim was full aircraft nose up. The flaps were up. One blade of the three-bladed Kiev Prop propeller was embedded approximately 18inches in the earth. The propeller blade was cracked laterally but not broken, and displayed only radial scores, indicating that it was not rotating when it dug in. The wreckage was taken to the TSB regional examination facility. The instruments and global positioning system (GPS) were removed and examined by the TSB Engineering Laboratory. The vertical speed indicator had a very heavy pointer mark at 830feet per minute (fpm) down that was attributed to impact, and the airspeed indicator had a faint counter-weight mark in the range of 20to 40mph. The GPSyielded time, position, and altitude information indicating that the aircraft climbed at 60to 65mph indicated airspeed and reached a maximum height of 322feet agl before beginning the final dive. The flight path is shown in AppendixA and the flight data derived from the GPS and other known data are presented at AppendixB. The Rotax 912UL-2 engine, serial number 4401361, was sent to Rotech Research Canada Limited, the Canadian factory representative for Rotax engines, and was examined by TSB and company personnel. Rotational scrape marks on the inside of the plastic ignition cover, as a result of contact with the flywheel, indicate that the engine was operating at the time of impact. It was not possible to determine the power being produced. The impact forces damaged one ignition system,2 rendering it inoperable, and detached one carburettor, resulting in engine stoppage at impact. With a low-inertia propeller, the engine stopped rotating before the aircraft came to rest, and the propeller did not have rotation damage. Discrepancies were noted in the fuel system including primer ports that were not capped, an in-line fuel filter that was installed backwards with two hose clamps on the outlet side of the filter and one clamp on the inlet side, and a loose fitting on the gascolator. These conditions could allow air to be introduced to the suction side of the fuel pump's primary feed line causing inadequate fuel flow and loss of engine power. The air filters were dirty and were distorted as a result of the impact. When the ignition trigger was reinstalled, the carburettors were reattached, and a serviceable fuel/air system was attached, the engine ran smoothly and produced full power. The SeaRey is a two-seat, tube, fabric, and composite amphibious aircraft that is built from a kit manufactured by Progressive Aerodyne, Inc. The type can be registered in either the ultralight or the amateur-built category. There are 22SeaRey aircraft registered in Canada, 9amateur-built, 11 advanced ultralights, and 2basic ultralights. The aircraft kits do not include cockpit furnishings, control panel, and other controls. The individual builder provides the material and designs the installation to suit the owner's needs. In C-GCWR, the electrical trim and electrical flaps were controlled by four push-button switches in a diamond arrangement on the top of the control stick. The fore and aft switches activated aircraft nose-down and aircraft nose-up pitch trim, respectively, while the switches to the left and right activated the flaps down and up, respectively. The switches were exposed and the pilot was known to have inadvertently activated the flaps or trim during previous flights. Take-off configuration for the SeaRey is flaps 20, trimmed fully aircraft nose up. Best angle climb is obtained at 60mph, flaps 20. Best rate climb is at 65mph, flaps 10. Flaps are not normally retracted to 10 until a speed of 60to 65mph is reached. On the day of the occurrence, the lead aircraft climbed at 60mph with flaps 20. Airport patterns are normally flown at 70mph, flaps 10, and final approach at 70mph, flaps 20. Best glide speed for the SeaRey is 70mph with flaps 10, which will give an engine-off rate of descent of 650fpm. With flaps up, the rate of descent is about 700fpm at 72mph and as much as 1000fpm at lower speeds. The aircraft is known to be susceptible to increased rates of descent if airspeed is allowed to drop below 1.3Vs on final approach.3 The aircraft is normally trimmed fully aircraft nose up for take-off because of the nose-down pitching moment of high power on the high-mounted engine. Control forces are relatively light and manageable in mis-trim situations. Wings level, the aircraft typically stalls with a classical g-break at all flap settings. Full aft elevator control input is required to reach the stall. There is no pre-stall buffet. Stall recovery is accomplished by lowering the nose and applying power. The aircraft normally recovers with an altitude loss of less than 100feet. In accelerated stalls, recovery is immediate on relaxation of aft elevator control with minimal altitude loss. Aileron control is effective at the stall. The aircraft displays no propensity to spin. The aircraft's characteristics were verified during the investigation by flying another SeaRey. The flying qualities of C-GCWR were not known to deviate from those characteristic of the type. According to the "Special Certificate of Airworthiness (Amateur-Built)," C-GCWR had a maximum gross weight of 1500pounds. The climb report submitted to Transport Canada to satisfy the requirements of Section549.111 of the Canadian Aviation Regulations (CARs) indicated a rate of climb of 400fpm. The gross weight at the time of the accident was estimated to be between 1250and 1300pounds with a mid-range centre of gravity. With this loading, the wings-level stall speed was estimated to be approximately 50mph with flaps up, 42mph with flaps20. Tests by the kit manufacturer indicate that, in the event of an engine failure during climb out, a minimum of 450feet of altitude is required to carry out a 180-degree turn and land. This is based on an initial condition of 65to 70mph and flaps 20, a representative speed and configuration for a normal climb after take-off. To accomplish this, the nose was pushed over immediately upon loss of power to an attitude of about 20nose down while simultaneously rolling into a 45bank turn. As soon as the aircraft had turned through 180degrees, it was rolled out and flared. These tests were carried out by an experienced company demonstration pilot. It was noted that the aircraft is a low-inertia high-drag machine, making loss of airspeed easy, but the regaining of it difficult. To regain 10mph of speed requires a lot of nose-down attitude and a few hundred feet of altitude loss.